CAREER: Development of Continuous-Flow Laser-Spin Polarized Xe-129 NMR Spectroscopy in Magnetic Stray Fields for the Investigation of Nanoporous Materials

在这个由化学部门实验物理化学项目资助的项目中，Meersmann将把连续流激光自旋极化129Xe核磁共振波谱与脉冲场梯度扩散技术结合起来，开发一种非侵入性分析技术，可以研究多孔基质材料的孔隙度、孔隙大小分布和孔隙连通性。将杂散磁场与连续流激光极化氙核磁共振（NMR）相结合，用于研究具有小扩散常数的材料的长程结构秩序。用这种新技术将探索的一个重要系统是由非常缓慢的单文件扩散过程驱动的一维纳米通道中的气体动力学。通过这些实验，可以首次探索氙线形状与扩散或协同簇扩散的关系等各种新现象。将开发一种非侵入性分析技术，以提供有关多孔材料的孔隙度，孔隙大小分布和孔隙连通性的信息。纳米通道在广泛的工业催化、地质和生物过程中发挥着重要作用。本研究的结果有望对多相催化、分离过程的材料科学以及对基础物理化学的理解做出重大贡献。研究生和本科生将参与本研究。他们将在前沿研究技术方面获得优秀的培训，为深造或进入科学/技术队伍做准备。

In this project funded by the Experimental Physical Chemistry Program of the Chemistry Division, Meersmann will combine continuous-flow laser-spin-polarized 129Xe nuclear magnetic resonance spectroscopy with pulsed-field-gradient diffusion techniques to develop a non-invasive analytical technique that allows the study of porosity, pore-size distribution and pore connectivity in porous host materials. A combination of magnetic stray fields with continuous flow laser polarized xenon Nuclear Magnetic Resonance (NMR) will be used to study long range structural order in materials with small diffusion constants. An important system that will be probed with this new technique is the gas dynamics in one-dimensional nanochannels that is driven by very slow single-file diffusion processes. A variety of novel phenomena such as the correlation of xenon lineshape with diffusion or concerted cluster diffusion can be probed for the first time with these experiments. A non-invasive analytical technique will be developed to provide information about the porosity, pore-size distribution and pore connectivity of porous materials. Nano-channels play an important role in a wide range of industrial catalytic, geologic and biological processes. The results of this research are expected to make a significant contribution to material science concerned with heterogeneous catalysis, separation processes and in the understanding of fundamental physical chemistry. Graduate and undergraduate students will participate in this research. They will gain excellent training in forefront research techniques in preparation for advanced studies or entry into the scientific/technological workforce.